By Lesley Wroughton WASHINGTON (Reuters) - The United States said on Thursday it was important to partner with Russia to help bring Syria's warring sides together for a proposed peace conference despite Moscow's financial and military backing for President Bashar al-Assad. Assad told Lebanon's Al-Manar television that Russia is committed to implementing a 2010 contract for S-300 air defense missiles. A Russian defense ministry source said the missiles had not been sent yet.

Syrian President Bashar al-Assad said on Thursday there was "popular pressure" to open a military front against Israel on the Golan Heights, which the Jewish state has occupied since 1967. "There is clear popular pressure to open a new front of resistance in the Golan," Assad said in an interview with Al-Manar, the television channel of his ally, Lebanon's Shiite Hezbollah movement. "There are several factors, including repeated Israeli aggression," he said. rd/ram/srm/hc

Germany and Canada on Thursday called on the Syrian opposition to take part in a US-Russian peace initiative after rebels said they would enter no talks until Hezbollah withdraws from the war. "The best chance for a lasting solution to the conflict in Syria is a sustainable political process," German Foreign Minister Guido Westerwelle said during a visit to Canada.

Russia has delivered to Syria promised air defence missiles, President Bashar al-Assad implied in an interview to be aired Thursday, in a move aimed at deterring foreign intervention in the more than two-year conflict. Moscow, the Assad regime's most powerful ally, announced this week it intends to honour its contract to supply Syria with the advanced S-300 missiles. The opposition National Coalition, meeting in Istanbul, said it would not take part in a US-Russian peace initiative dubbed Geneva 2 "so long as the militias of Iran and Hezbollah keep up their invasion".